Perspectives on the beautiful game of soccer; fueled by enormous amounts of coffee

Friday, June 6, 2008

Give me your stats, your theories

Your huddled facts yearning to breathe free.

Yay for readers who email me intriguing material. I wasn't a math major, so I wouldn't run these type of numbers myself, but it's an interesting analysis. One thing I do know is that it's incredibly hard to beat the Costa Rican national team on their turf field at Saprissa.

This info comes courtesy of R. Bruce, who decided to analyze the impact of artificial surfaces in MLS.

Beyond the aesthetic discussion - (Does it bastardize the game? Does it cause more injuries?) - there's this question: Do teams that play home matches on FakeTurf gain an unfair advantage?

I looked at MLS matches only from 2004-present. Pre-2004 matches were played under non-standard rules where shootouts and golden goals produced a lot more outright wins and losses. Whereas today, the draw in MLS is as common as in other leagues. With 3 points for a win but only 1 for a draw, the analysis felt tainted. Secondly, the sample of matches played on turf prior to 2004 was fairly small. Since 2004, Real Salt Lake and Toronto FC have entered the league and New York (2003, actually) and New England (2007) have also begun playing on FakeTurf.

The league-wide average the last 4+ years is 1.651 points at home for every 1 point earned on the road. But for teams playing on turf, it's 1.847 ppg at home for every 1 point earned away. Clearly, turf teams are significantly more successful when they play on their FakeTurf compared to other teams playing at home on real grass.

So, it seems they do gain a clear advantage by having greater familiarity with the FakeTurf.

Anon's question boils down to whether the players can be simultaneously acclimatized to both kinds of surfaces.

I think its weird that the author disregards injuries as merely an 'aestetic' issue of playing on turf. In fact, it seems to me to be the most important question. Everyone can practice on turf if they want to improve their turf performance. But, if turf is worse for the players, should they refuse to play on it (Reyna?)? Should the league ban it?

The teams that do have turf fields should study this as well, because they are at a competetive disadvantage if they are losing more players to turf-related injuries than the grass teams.

Also, there must be some way of statistically analyzing the injury problem. Although, it would probably be trickier than the simple win percentage. Might be able to compare injury rates for each year to the ratio of turf games to grass games for that year. I'm not sure if the sample size is big enough yet, nor whether the injuries are reported in sufficient detail to make this work, though.